The sum of the measures of the interior angles of a polygon is 720°. How many sides does the polygon have?

Mathematics · Middle School · Tue Nov 03 2020

Answered on

Given the statement:

The sum of the measures of the interior angles of a polygon is 720°. 

Determine how many sides does the polygon has.

Solution:

We all know that the a hexagon with 6 sides has an interior angle sum of 720 degrees, hence, this can be solved using the formula.

S = (n − 2) × 180°

S = Sum of the interior angles

n = number of sides

Solve for n.
Divide both sides by 180°.

720° = (n − 2) × 180°

720°/180° = (n − 2) × 180°/180°

4 = n - 2

Transpose -2 to the other side of the equation, hence it must be taken to note that in transposing a number, the sign changes.

n = 4 + 2

n = 6

Final answer:

Number of sides = 6